[RFC][PATCH 2/3] iommu/fsl: Add iommu domain attributes required by fsl PAMU driver.

[b16395 at freescale.com]

From: Varun Sethi <Varun.Sethi at freescale.com>

Added the following domain attributes required by FSL PAMU driver:
1. Subwindows field added to the iommu domain geometry attribute.
2. Added new iommu stash attribute, which allows setting of the
   LIODN specific stash id parameter through IOMMU API.
3. Added an attribute for enabling/disabling DMA to a particular
   memory window.

Signed-off-by: Varun Sethi <Varun.Sethi at freescale.com>
---
 include/linux/iommu.h |   30 ++++++++++++++++++++++++++++++
 1 files changed, 30 insertions(+), 0 deletions(-)

diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 7e83370..eaa40c6 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -44,6 +44,28 @@ struct iommu_domain_geometry {
 	dma_addr_t aperture_start; /* First address that can be mapped    */
 	dma_addr_t aperture_end;   /* Last address that can be mapped     */
 	bool force_aperture;       /* DMA only allowed in mappable range? */
+
+	/* The subwindows field indicates number of DMA subwindows supported
+	 * by the geometry. Following is the interpretation of
+	 * values for this field:
+	 * 0 : This implies that the supported geometry size is 1 MB
+         * with each subwindow size being 4KB. Thus number of subwindows
+	 * being = 1MB/4KB = 256.
+	 * 1 : Only one DMA window i.e. no subwindows.
+	 * value other than 0 or 1 would indicate actual number of subwindows.
+	 */
+	u32 subwindows;
+};
+
+/* This attribute corresponds to IOMMUs capable of generating
+ * a stash transaction. A stash transaction is typically a
+ * hardware initiated prefetch of data from memory to cache.
+ * This attribute allows configuring stashig specific parameters
+ * in the IOMMU hardware.
+ */
+struct iommu_stash_attribute {
+	u32 	cpu;	/* cpu number */
+	u32 	cache;	/* cache to stash to: L1,L2,L3 */
 };
 
 struct iommu_domain {
@@ -60,6 +82,14 @@ struct iommu_domain {
 enum iommu_attr {
 	DOMAIN_ATTR_MAX,
 	DOMAIN_ATTR_GEOMETRY,
+	/* Set the IOMMU hardware stashing
+	 * parameters.
+	 */
+	DOMAIN_ATTR_STASH,
+	/* Explicity enable/disable DMA for a
+         * particular memory window.
+         */
+	DOMAIN_ATTR_ENABLE,
 };
 
 #ifdef CONFIG_IOMMU_API
-- 
1.7.4.1